Motor-starting device.



W. O. LUM.

MOTOR STARTING DEVICE.

APPLICATION FILED JULY 18, 1907.

Patented Mar.23,1909.

Inventor:

Walter O. Lum

UNITED STATES PATENT OFFICE.

WALTER O. LUM, OF SCHENECTADY, NEW YORK, ASSIGNOR TO GENERAL ELECTRIC COMPANY A CORPORATION OF NEW YORK.

INIOTOR-STARTIN G DEVICE Specification of Letters Patent.

I Patented March 23, 1909.

Application filed Jul 1,8, 1907. Serial No. 384,438.

To all whom it may concern:

l3e it known that I, WALTER O. LUM, a citlzen of the United States, residing at Schenectady, county of Schenectady, State of NewYork, have invented certain new and useful Improvements in Motor-Starting DetVi es, of which the following is a specificaion.

This invention relates to devices for controlling electric circuits and has for its object the provision. of a device of this charac ter whereby an' electric'motor may be auto matically controlled in a very reliable, safe and efficient manner by the simple closing of a control switch.

In carrying out my invention, I provide in connection with the starting resistance, which is included int-he circuit of the motor, a controlling element which has a bias to-' ward the initial or starting position. Upon the closing of the control circuit, the controlling-element is moved by means of a solenoid against the bias to cut out the resistance. When the element reaches running position, orthe point at which the resistance 1s all cut out of circuit, the solenoid is denergized, and the controlling arm returns in response to itsbias to the starting position. The controlling arm has in the meantime, been shortcircuited so that it does not afiect the resistance. preferably use electromagnetic switches for cutting out the resistance, and control the switches by means of the controlling element.

In' order to insure that the controlling arm will always be in the starting osition when the armature circuit is ClOSGf, I arrange an electromagnetic switch for closing thearmature circuit, which switch also controls the circuit of the operating solenoid. This switch cannot be energized until the controlling arm is in the off position. The electromagnetic switches are so arranged and connected that when they are energized and operated to cut out the resistance, they short-circuit the controlling arm and remain closed, independent of said arm. In this way the circuit is not broken at the control-- ling element. When the controlling element has been moved so as to energize all of thrswitches and cut out the, resistance, the conneetion's are such that the last switch will de energize all of the former ones. p

In the accompanying drawing, in which I have sh own my invention embodied ,for pur' With the larger type of motors, I

poses of illustration, in a concrete form, 1 is the controlling element of the master controller pivoted at 2 and operated so that its free end engages the contacts 3 to vary the resistance of the circuit of armature A. This controlling element is operated by means of a solenoid 4 acting upon a core 5, to which the arm is pivoted at 6. A dash-pot 7, the barrel of which is pivoted to the core, and the plunger 8 pivoted to a fixed support is arranged so as to retard the core and hence the arm 1 in its upward movement, but will allow the parts to drop freely.

I have shown my invention adapted for a relatively large type of motor in which it is preferable to havethe resistance switches operated electromagnetically, the circuit of these switches being controlled by the controlling arm 1. These switches A, B, C, and D are all identical in construction, and each consists of a solenoid 9 operating a core 10, to the upper end of which is secured a bridging contact 11, adapted to bridge contacts 12, and at their lower end a similar bridging contact 13, bridging the contacts 14. Another electromagnetic switch E has a solenoid provided with an actuating coil 15 and a holding coil 16, while the core 17 has two contactors, 18 and 19, cooperating respectively with contacts 20 and 21. Another electromagnetic switch F, also provided with a lifting coil 22 and holding coil 23, has its core 24 provided with a bridging contactor 25 adapted to engage contacts 26. The circuit V of the lifting coil 22 is controlled through contacts 27, which are arranged to be bridged by contactor 28 mounted upon, but insulated from, the controlling arm 1. A manually-operated switch 29 controls the device.

The arrangement of circuits of operation are as follows :With the arts in the position shown in the figure, Which is the position of rest, when the switch 29 is closed, the holding coil 23, which is connected across the line, and the lifting coil 22, which is energized through the contactor 28 will be energized. This will cause the contacts 26 to be bridged by contactor 25 to close the-armature circuit from the main across contacts 26through conductor 30, armature A, conductor 31, resistances R R R R and R, back to the main. At the same time, solenoid 4 will be energized from the main through conductor 31 across contactor 19,

and the mode I conductor a solenoid 4 and conductor 33 back to the main. This draws up core 5 and the arm is moved on to the first of contacts 3. When this contact is made, a circuit is completed from conductor 31, conductor 32 through the coil 9, conductor 34, contact 3, arm land conductor 35, back to the main. This causes-contacton 13 to bridge contacts 14 and cut out section B of the resistance, the armature circuit now being through sections R R R and R thencethrough conductor 36, contactor'13, conductor 37 back to the main. At thesame time, the contacts 12 are bridged by the contactorjll so that the conductor. 34, arm 1 and conductor 35 are short-circuited from the point: across to point 39.

- second one, there will be no sparking since the arm is short-circuited. The solenoid 9 will also remainlenergized after the arm has passed to the next contact because, of this short-circuit. A similar action occurs when the arm passes on to the second, third'and fourth contacts, i. a, the solenoid switches B, C and D will be successively energized to cut out sections R, R and R resistance, the controlling; arm each time being vshort-circuited as above described. VVhenthe controlling arm reaches the last of contacts 3, the lifting coil 15 of electromagnetic switch E will be energized, the holding coil 16 hav- "ing been connected across the line when opened at the contacts 21.

' time by opening a line switch.

switch F was closed. This will cause .the last section R of the starting resistance to be short-circuited by the contactor 18, and at the same time bridging contact 19 will be lifted so as to open the control circuit at con tacts 21. This will denergize the coils of switches A, B, C and D -and.allow them to drop and will also denergize the lifting coil 15 of switch This latter switch, however, will be held closed by the/holding coil 16.

- The circuit of solenoid 4 is likewise opened,

and the controlling arm drops in response to its bias back to its starting osition, and the contacts 27 are bridged. T e lifting coil 15 will not be energized because its circuit is Upon failure of voltage, holding coils 23 and 16 permit the armature circuit to be opened at switchesE and F, and the motor may be stop ed at any n case the arm 1 should stick, or in any way be pre- Now, when the arm moves off of the first contact 3-and on to they arenas It will be understood, of course, that v'arious modificatlons of my mvention willyug;

' vention, the scope of which is set forth in the annexed claims.

What I claim as new and desire t secure by Letters Patent of the United Sta es, is, -1. An automatic. motor starter, comprising a series of contacts, a circuit-controlling element therefor having a bias to starting position, an electrically controlled device for moving said element to running position, and means for deenergizing said-device and releasing said element when the latter reaches running position.

2. An automatic motor starter, compris ing a series of contacts, a circuit-contr0lling element therefor having a bias to starting.

osition, an electrically controlled device for moving sald element to running position,

means for retarding said element during said movement, and means for deenergizing said device and releasing said element when the latter reaches running position.

3. 'An automatic motor starter, com rising a series of contacts, a circuit-contro ling element therefor having a bias to starting position, an electromagnetic switch arranged to close the armature circuit only when the element is in said position, an

electrically controlled device for moving said element to running position, and means for denergizing said device and releasing said element when the latter reaches running position.

a 4. An automatic motor starter, comprising'a'series of contacts, a circuit-controlling element therefor having a bias to starting position, an electromagnetic switch arranged to close the armature circuit and the circuit of said device only when the element is in said position, an electrically controlled device for moving said element to running position, and means for deenergizingvsaid device and releasing said element when the latter reaches running position.

5. An automatic motor starter, comprising a series of contacts, a circuit-controlling element therefor having a bias to starting position, an electromagnetic switch arranged to close the armature circuit only when the element is in said position, an electrically controlled device for moving said element to running position, means for retarding said element during said movement, and means for deenergizing said device and releasing said element when the latter reaches running position.

6. An automatic motor starter, comprising a series of contacts, a circuit-controlling element thereforhaving a bias to starting position, an electrically controlled device for moving said element to running 1 for denergizing said e ectrically controlled device and releasing said. element when the latter reaches running position.

7. An automatic motor starter, comprising a plurality of electromagnetic resistance-varying switches, a circuit-controlling element therefor having a bias. to starting osition, an'electrically controlled device or movin said element to successively energize sai switches, and'means for denergizing said device and releasing said element when-the latter reaches running posi- I ing a plurality of electromagnetic resistancetion.

prising a plurality of electromagnetic resistance-varying switches, a circuit-controlling element therefor having a bias to starting position, an electromagnetic switch arranged to close the motor circuit only when the controlling element is in starting position, an electrically controlled device for moving said'element to successively energize said switches, and means for denergizing said device and releasing said element when the latter reaches running position.

9, An automatic motor starter, comprisng a plurality of electromagnetic resistancevaryin switches, a circuit-controlling elementtherefor having a bias to starting position, an-.electrically controlled device for moving said element to successively energize said switches, an electromagnetic switch arranged to close the motor circuit and energize said device only when the controlling element is in the startin position, and. means for denergizing said evice and releasing said element when the latter reaches running position.

10. An automatic motor starter, comprising a plurality of-electromagnetic resistancevarying switches, a master controlling element trically controlled device for moving said element to successively energize said switches, and connections whereby each of said switches is operated to short-circuit the controllim element and is kept energized independently of said element.

11. An automatic motor starter comprising a plurality of electromagnetic resistance-.

varylng switches, a master controlling element biased to an initial position, .an electrically controlled device formovin said element to successively energize sai switches, connections whereby each of said switches is operated to short-circuit the controlling element and is kept energized independently of said element, and means for deenergizing said devlce when said element has been moved to energize said switches.

'8. An automatic motor starter, com-.

biased to an initial position, an elec- 12. An automatic motor starter, comprising a plurality of electromagnetic resistancevarying switches, a master controlling element biased to an initial position, an electrically controlled device for moving said element to successively energize said switches, an electromagnetic switch arranged to close the motor circuit and energize said device only when the controllinglarm is in the initial position, connections whereby each of said switches is operated to short circuit the controlling element and is kept energized independently of said element, and means for deenergizing said device when said element has been moved to energize said switches. I

13. An automatic motor starter, comprisvarying switches, a master controlling element 'biased to an initial position, an electrically controlled device to move said element to successively energize saidswitches, connections whereby each of said switches is operated to short-circuit the controlling element and is kept energized independently of said element, and means whereby the closing of the last of said switches deenergizes the others.

14. An automatic motor starter, comprising a plurality of electromagnetic resistancevarying switches, a master controlling element blased to an inltlal position, an electrically'controlled device for moving said element to successively energize said switches,

connections whereby each of said switches is operated to short-circuit the controlling element and is kept energized independently of said element, means for denergizing said device when said element has been moved to energize said switches, and *means'whereby the closing of the last of said switches deenergizes the others. I

'15. An automatic motor starter, comprising a plurality of electromagnetic resistancevarying switches, a master controlling'ele ment biased to an initial'position, an electrically controlled device for moving said element to successively energize said switches, an electromagnetic switch. arranged to close the motor circuit and energize said device only when the controlling element isin the initial position, connections whereby each of said switches is operatedto short-circuit the controlling element and is kept energized independently or said element, means for deene'rgizing said device when said element has been moved to ener ize said switches, and means whereby the c osing of the last of said switches dener izes'the others.

In witness w ereof, I have hereunto set my hand this 16th day of July, 1907.

- WALTER O. LUM. Witnesses: BENJAMIN B. HULL. HELEN ORFORD. 

